高强钢管超高强混凝土柱抗震性能试验研究

EXPERIMENTAL STUDY ON QUASI-STATIC BEHAVIOR OF ULTRAHIGH STRENGTH CONCRETE FILLED HIGH STRENGTH STEEL TUBULAR COLUMNS

以轴压比、含钢率和钢材强度为参数,进行了8根高强钢管超高强混凝土柱和1根普通强度钢管超高强混凝土对比柱的拟静力试验,分析了各参数对破坏形态、荷载-位移滞回曲线、骨架曲线和各个抗震性能指标(如延性、耗能和强度与刚度退化等)的影响程度。结果表明:压弯破坏为主要破坏模式;弹性刚度受轴压比影响不大,但受含钢率和钢材强度影响较大;极限承载力受轴压比、含钢率和钢材强度影响较大,随前者增大而降低,随后两者增大而增大;延性受轴压比、钢材强度和含钢率影响较大,随前两者增大降低,随后者增大而增大;耗能能力随轴压比增大而减弱,随含钢率和钢材强度增大而增强;刚度和强度退化程度随轴压比增大而降低,随含钢率增大而增大,且前者随钢材强度增大而增大,后者则随钢材强度增大呈减小趋势。通过对比不同规程抗弯刚度计算方法,结果表明:受材料适用范围限制,各规程不适用于该类高强材料组合构件。

Taking axial compression ratio,steel ratio and steel strength as parameters,eight quasi-static tests on UHSC filled high strength steel tubular columns and one UHSC filled normal strength steel tubular columns were carried out to analyse the effects on failure mode,load displacement hysteretic curve,skeleton curve,as well as the seismic performance indexes such as ductility,energy consumption,strength and stiffness degradation.The results show that overall bending is the main failure mode.The elastic stiffness remains unchanged as axial compression ratio changes,but changes a lot as steel ratio and steel strength change.The ultimate bearing capacity is greatly affected by axial compression ratio,steel content and steel strength,which decreases with the former increases,and increases with the latter two increases.The ductility is greatly affected by axial compression ratio,steel strength and steel strength,which decreases with the increase of the former two,and increases with the increase of the latter.The degradation in stiffness and strength decrease when axial compression ratio increases,but increase as steel ratio increases,while the former increases and the latter decreases when steel strength increases.Comparing the bending stiffness calculation methods of different codes,due to the limitation of material application,the codes are not suitable for this kind of high-strength material composite members.